TLS server impersonation via hostname-blind certificate policy
Published Nov 22, 2021 · Updated Aug 4, 2024
Improper certificate validation in AWS IoT Device SDK v2 on macOS allows man-in-the-middle attackers to impersonate TLS servers. The Apple TLS backend creates a basic X.509 policy with SecPolicyCreateBasicX509 instead of a hostname-aware SSL policy when a custom root CA is configured. Exploitation requires a macOS client using an overridden CA and an attacker able to intercept its network path, enabling disclosure or modification of protected IoT traffic.
Summary
What happened
Improper certificate validation in AWS IoT Device SDK v2 on macOS allows man-in-the-middle attackers to impersonate TLS servers. The Apple TLS backend creates a basic X.509 policy with SecPolicyCreateBasicX509 instead of a hostname-aware SSL policy when a custom root CA is configured. Exploitation requires a macOS client using an overridden CA and an attacker able to intercept its network path, enabling disclosure or modification of protected IoT traffic.
The record
- CVE
- CVE-2021-40829
- Published
- Nov 22, 2021
- Updated
- Aug 4, 2024
- Vendor
- Amazon Web Services
- Product
- AWS IoT Device SDK v2 for Python
- Classifications
- CWE-295, T1557
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Nov 22, 2021CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=unspecified <1.6.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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